Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Stay on top of the latest market trends

Subscribe to Axios Markets for the latest market trends and economic insights. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Axios on your phone

Get breaking news and scoops on the go with the Axios app.

Download for free.

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Pavement, buildings, and other impervious surfaces have grown over time in the Washington, D.C. metro area. The brightest colors have the clearest signature of pavement. (Credit: Xiao-Peng Song, Texas Tech University using Landsat imagery)

In many areas, the Brood X cicadas that are emerging across a 15-state region are spottier in their prevalence than they were 17 years ago. Some neighborhoods have been inundated with the insects, while others are seeing only a few.

Why it matters: The 17-year periodical cicadas are one of nature's wonders, but the patchiness of the emergence, particularly in suburbia, points to one of the key threats to these unique insects: urbanization.

The big picture: America's cities have expanded at a rapid rate during the past few decades, with sprawl spreading out far beyond city centers. In Washington, D.C., a 2016 study using satellite data found a rapid expansion in impervious ground cover, such as pavement and buildings, from the mid-1980s through 2010.

  • That trend has likely continued through the present day, says study co-author Xia-Peng Song of Texas Tech University.
  • Much of the growth in the Washington region has occurred along and beyond the Beltway that rings the city, particularly to the west, in Tysons Corner and Springfield, as well as College Park and New Carrollton.
  • Knocking down trees to construct new homes, businesses and parking lots can kill the insects or block their emergence, since immature cicadas feed upon their roots while underground, University of Maryland entomologist Paula M. Shrewsbury tells Axios.

What's happening: The two biggest threats to periodical cicadas, which emerge every 13 or 17 years, are urbanization and climate change, Shrewsbury says.

  • "Even if they're close to the end of the [17-year] cycle, they can't get out from underneath the pavement. It's not like they can travel, you know 100 feet or 200 feet and find another way out, that's not happening," Shrewsbury says.
  • There are already two periodical cicada broods that have gone extinct, one in Connecticut and another in Florida, she says, and scientists are keeping close watch on a group in Long Island. Urban development there may be wiping out that population, scientists fear.

Climate change also poses a threat to cicadas because warming temperatures could alter the timing of their emergence, or encourage interbreeding between 13-year and 17-year populations. That would reduce the number of cicadas emerging in any given year.

  • And that's a big problem (for the cicadas), since the insect's main defense mechanism against predators is "predator satiation" — meaning there are so many cicadas emerging at once that predators can eat as many as they want, yet many of the insects will still survive long enough to lay their eggs.
  • Cicadas help feed species ranging from various types of small birds to turkeys and squirrels, with their decomposing exoskeletons helping to add nutrients into soils to boost tree growth.
  • Perhaps more importantly, they've been successfully following this unique life cycle for generations, so any trouble now is a warning sign for humans.

Our thought bubble: The periodical cicadas are a reminder that we now live in an era known as the "Anthropocene," as human forces are re-shaping the planet. This is harming biodiversity, driving climate change, and having a host of other effects worldwide.

What's next: You can track cicadas in your area through the Cicada Safari citizen science app.

Go deeper

Women are leading the new Latin American literature boom

Photo illustration: Sarah Grillo/Axios. Photos: David Levenson, Ray Tang/Anadolu Agency/Getty Images

Gone are the whimsical elements, and in come the suspense, the gothic and the noir. The new Latin American Boom is here, and it is being led by women.

What’s happening: Writers like Argentines Samanta Schweblin and Mariana Enríquez, Mexican Fernanda Melchor and Chilean Lina Meruane have made international waves with books that comment on quotidian violence — gender and otherwise — as well as othering through pulse-racing, enthralling and occasionally beautiful horror.

Updated 30 mins ago - Sports

Olympics dashboard

Suni Lee. Photo: Jamie Squire/Getty Images

🥇 : U.S. gymnast Suni Lee wins gold in the women's individual all-around

🤸🏾‍♀️: Simone Biles reacts to "love and support" after withdrawing from all-around gymnastics and team finals, citing her mental health

🏃: U.S. pole vaulter Sam Kendricks withdraws from Games after positive coronavirus test

🏊‍♂️: Caeleb Dressel wins gold in men's 100m freestyle —Bobby Finke wins gold in first men's Olympic 800m freestyle

📷: In photos: Tokyo Olympics day 6 highlights

🗓: The Olympic events to watch today

🏃‍: Female Olympians push back against double standard in uniforms

Go deeper: Full Axios coverage

Heat dome sends temperatures soaring from Oregon to Louisiana

Forecast maximum temperatures (darker red shading represents the hottest temperatures, in the upper 90s to low 100s, Fahrenheit). July 29. Image: WeatherBell

The Pacific Northwest is once again in the midst of a heat wave after already seeing its worst such event on record this summer. Temperatures are soaring into the low 100s in some areas, while dangerous heat is also affecting the South Central states and Gulf Coast.

Why it matters: The occurrence of yet another heat wave during a drought in the West is ratcheting up wildfire risks. The heat itself is a major public health risk, as extreme heat is typically the biggest annual weather-related cause of mortality in the U.S.